June Gardening Calendar

·         Lawn Care

·        Mow lawn frequently, keeping it at a 2 to 2 ½ inch height.   Mow often enough so that you are not removing more than 1/3 of the total height at a time.

·        Fertilize lawn with Stein’s Weed Control plus Lawn Food® to decrease dandelions and broadleaf weeds. 

·         Gardening

·        Water early in the morning to reduce the risk of disease and water loss to evaporation.

·        Apply organic mulch when soil has warmed up completely.

·        Plant warm weather crops (eggplant, lima beans, peppers) and late potatoes.

·        Start Brussels sprout seeds now so they can be transferred into your garden mid-July.  They will be ready for harvest after the first frost in fall.

·        Locate a well-drained area to start a compost pile.

·         Plantings

·        Be sure to keep all newly planted shrubs, evergreens, perennials and roses well watered, especially during hot, dry spells.

·        Plant balled and burlapped and container grown trees and shrubs.  Apply a 2 to 3 inch layer of shredded mulch around the shrubs to conserve moisture and reduce weeds.

·        Finish pruning spring-flowering shrubs such as lilacs and forsythia.

·        If desired, transplant bleeding hearts (Dicentra).

·        Apply organic mulch to flower beds when soil has warmed up completely.

·        Pinch back mums and asters.  Keep them 4 to 6 inches tall throughout June.

·        Cut back delphiniums after they have bloomed.

·        Stake tall growing lilies, dahlias and gladiola.   

·        Remove faded peony blossoms.  If you wish to bring some peony blooms indoors, be sure to cut them well before they have fully opened. 

·        Wrap fruit tree trunks with sticky tape or bands to discourage insects.

·        This is a great month to plant potted roses. 

·        Roses - Tie canes of climbers and ramblers to a fence, trellis or other support.

·        Check burning bush and other euonymus for signs of the euonymus caterpillar. These worm-like insects build webbed nests that can be removed and destroyed by knocking out the nests with a stick.  Treat large populations with Thuricide by Bonide® as its active ingredient kills caterpillars without harming beneficial insects, wildlife or people.

·        Check young trees once or twice a week and water them thoroughly as needed.  Moisture loving trees, such as paper birch, may need to be watered once a week during dry weather.

·        Start checking crabapples, birches and other ornamental trees for webbed nests built by Eastern tent caterpillars.  Remove and destroy all nests. 

·        Watch for signs of gypsy moth larvae.  These worm-like insects eventually grow to two inches long and have two rows of red and blue warts on their backs.  Often, you can catch and destroy them as they crawl down tree trunks in search of shade during the day. 

·        Watch for fire blight on crabapple trees. The leaves turn black and branch tips will curl.  Avoid pruning crabapple trees during wet periods.  Prune out infected branches below the canker (sunken, discolored area) on the stem.  Always disinfect pruning tools between cuts.

Mid-June

·         Gardening

·        Mix well-rotted manure with the soil in established strawberry plantings.

·        Thin newly emerged annuals and vegetables that were planted from seed in the garden.

·        Cover broccoli, cauliflower, cabbage and Brussels sprouts with a lightweight row cover to prevent cabbage worms from reaching and feeding on the plants.

·         Plantings

·        Chrysanthemums that will bloom in early September should be pinched back for the last time.

·        Try starting some perennials from seed.  Good candidates are Aquilegias, Delphiniums, Dianthus, Gaillardias, Lupines, Tanacetums, Violas and Veronicas.  Be sure to label all plantings.

·        Remove faded peony blossoms to encourage continuous blooms.

·        Dig and divide overgrown Siberian iris after they finish blooming.  It may take the divided ones more than a year to recover and bloom. 

·        Pinch out the tips of dahlias when they reach 15 inches to encourage branching and flowering.

·        Pinch back leggy tuberous begonias.

·        Remove faded flowers from blooming plants to keep them looking fresh and to encourage additional blooms.

·        Remove flowers on coleus as they appear to keep plants full and compact.

·        Remove flowers from lamb’s ear (Stachys) if you wish to encourage better foliage.

·        Pinch Russian Sage (shown right) and Sedum ‘Autumn Joy’ back by half if they have flopped in the garden in the past. 

·        Roses: Apply fungicides to control Blackspot fungal disease on roses now or at the first signs of disease.  Repeat every seven days throughout the growing season, but less often in dry weather.  Remove infected and fallen leaves throughout the season.

·        Remove faded flowers on repeat blooming roses and hybrid tea roses to improve the appearance and increase bloom time.  Remove individual flowers in the cluster as they fade.  Once all of the flowers in the cluster have bloomed, prune back the flower stem to the first 5-leaflet leaf.  Deadhead single-flowered roses back to the first 5-leaflet leaf.

·        Prune old garden, species, shrub and rambling roses.  (Shrub and species roses typically need very little pruning).

·        Prune climbing roses and deadhead faded flowers by pruning the flowering stems back to the third or fourth sets of leaves.

·        Continue to watch for phomopsis blight on junipers.  Infected plants have sunken discolored areas with brown and dead needles.  Prune out infected branches 9 inches below the canker, disinfecting your tool between each cut.

Late June

·         Lawn Care

·        Let your lawn grow longer during dry spells.

·         Gardening

·        Remove suckers (side shoots) that form between the leaf and stem on staked tomatoes when they reach 1 to 2 inches long to allow for an earlier, but smaller harvest.   

·        Be sure that fast-growing tomato plants have sufficient moisture.  Mulch heavily.

·        Stop harvesting asparagus and rhubarb by the end of the month.  Top-dress the beds with compost or well-rotted manure.

·        Plant sweet corn now.  It will make quick progress in the warm weather.  Stagger plantings five days apart for a longer harvest period in August.

·         Plantings

·        Houseplants can be taken outdoors for the summer if a sheltered spot can be found for them.  Protect from both direct sun and strong winds. Note:  Palms and ferns do not like strong sunlight.

·        Give quick-growing flowers plenty of water during dry spells.

·        Watch for metallic green and brown Japanese beetles. Pick by hand and destroy small populations. Larger populations may need a ready-to-use insecticide such as Bayer® Complete Insect Killer.

Sources:

Minnich, Jerry. The Wisconsin Garden Guide – The Complete Guide to Vegetables, Flowers, Herbs, Fruit, & Nuts, Lawn & Landscaping, Indoor Gardening. 3rd ed. Madison: Prairie Oak, 1995. Print.

Myers, Melinda. Month by Month Gardening in Wisconsin: What to Do Each Month to Have a Beautiful Garden All Year. Franklin: Cool Springs, 2006. Print.